ответить на вопросы на what factors account for the growing popularity of ballooning as a sport? why are most balloons used today of the hot-air variety? why have balloons captured the imagination for over two hundred years? why do people want to go up in a ballon?
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The basic idea behind hot air balloons has been around for a long time. Archemedes, one of the greatest mathematicians in Ancient Greece, figured out the principle of buoyancy more than 2,000 years ago, and may have conceived of flying machines lifted by the force. In the 13th century, the English scientist Roger Bacon and the German philosopher Albertus Magnus both proposed hypothetical flying machines based on the principle.